An electrowetting display apparatus is known inter alia from WO2003/071346. This known display apparatus includes an electrowetting display device and a display driving system. The display device has a plurality of display elements, each of which comprises a non conductive first fluid and an immiscible, polar second fluid. A display element has at least two electrodes, one of which may be in common with a plurality of display elements. When no voltage is applied to the electrodes the element is in an inactive state and the two fluids form two layers, both extending over the cross-section of the display element. On application of a voltage the element is in an active state and the first fluid is contracted and does not cover the entire cross-section of the display element anymore. When the first fluid is fully retracted, the element is in an open state. Depending on the optical properties of the first and second fluid, a display effect can be achieved for incident light that it is reflected or transmitted by the display element. The combined display effects of a plurality of elements in the display device produces an image for an observer.
A method of driving an electrowetting display device containing such display elements is known from WO2005/036517. The method uses the application of voltages to the elements which cause only a partial contraction of the first fluid, thereby producing grey level display states. The stability of the grey level display states is improved by applying a so-called pre-pulse before applying the signal level for the desired display state to the element. The pre-pulse sets the element in an initial state, thereby erasing a memory of previous display states of the element.
A disadvantage of the known method of driving is the inadequate quality of the image.
It is an object of the invention to provide a method of driving that improves the quality of the image.